asusf15/alpine-embeddings

Alpine Embeddings

Run embedding models locally on Alpine Linux in Docker using Node.js — zero Python, zero glibc, pure WASM inference.

What is this?

A lightweight REST API that generates text embeddings using transformer models. Runs entirely in a ~100MB Docker container on Alpine Linux with no native dependencies.

Feature	Detail
Runtime	Node.js 20 on Alpine Linux
Inference	ONNX Runtime (WASM backend) via @xenova/transformers
Model	Xenova/bge-small-en-v1.5 (384 dimensions, 32MB)
API	REST (Express.js)
Image size	~150MB
Startup	~5s (model loads from cache)
Latency	~50-100ms per embedding

Quick Start

# Clone
git clone https://huggingface.co/asusf15/alpine-embeddings
cd alpine-embeddings

# Build
docker build -t embeddings .

# Run
docker run -p 3000:3000 embeddings

Server starts on http://localhost:3000. Model loads automatically on first boot (~5s).

API

POST /embed

Generate embeddings for text.

Request:

{"text": "Hello world"}

Batch request:

{"text": ["Hello world", "Another sentence", "Third one"]}

Response:

{
  "embeddings": [[0.0011, -0.0146, 0.0203, ...]],
  "dims": 384,
  "model": "Xenova/bge-small-en-v1.5",
  "elapsed_ms": 52
}

GET /health

Health check.

{"status": "ready", "model": "Xenova/bge-small-en-v1.5"}

Usage Examples

cURL (Linux/Mac)

curl -X POST http://localhost:3000/embed \
  -H "Content-Type: application/json" \
  -d '{"text": "Hello world"}'

PowerShell (Windows)

Invoke-RestMethod -Uri http://localhost:3000/embed -Method Post -ContentType "application/json" -Body '{"text": "Hello world"}'

JavaScript (fetch)

const res = await fetch('http://localhost:3000/embed', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ text: ['Hello', 'World'] })
});
const { embeddings } = await res.json();
console.log(embeddings[0].length); // 384

Python (requests)

import requests
r = requests.post('http://localhost:3000/embed', json={"text": "Hello world"})
embedding = r.json()["embeddings"][0]  # 384-dim vector

Configuration

Set via environment variables:

Variable	Default	Description
PORT	3000	Server port
MODEL	Xenova/bge-small-en-v1.5	HuggingFace model ID

# Use a different model
docker run -p 3000:3000 -e MODEL=Xenova/all-MiniLM-L6-v2 embeddings

# Different port
docker run -p 8080:8080 -e PORT=8080 embeddings

Available Models

Any ONNX model from the Xenova collection works:

Model	Dims	Size	Quality
Xenova/bge-small-en-v1.5	384	32MB	⭐ Best for English
Xenova/all-MiniLM-L6-v2	384	22MB	Good, smallest
Xenova/bge-base-en-v1.5	768	110MB	Higher quality
Xenova/multilingual-e5-small	384	113MB	Multilingual

How It Works

The key challenge: onnxruntime-node (native ONNX runtime) requires glibc, but Alpine uses musl libc. The solution:

1. Install @xenova/transformers (which depends on onnxruntime-node)
2. Stub onnxruntime-node to re-export onnxruntime-web instead
3. onnxruntime-web uses WASM — runs on any OS/libc
4. Set numThreads = 1 (WASM workers not needed in Node.js server)
5. Copy WASM binaries to where transformers.js expects them

This gives you the full transformer inference pipeline (tokenizer + model) running in pure WASM on Alpine.

Project Structure

├── Dockerfile       # Alpine + Node 20, WASM stubbing
├── package.json     # @xenova/transformers + onnxruntime-web + express
├── server.js        # Express API with /embed and /health
├── preload.js       # (Optional) Pre-download model during build
└── .dockerignore    # Exclude node_modules from context

Sharing

Push to Docker Hub

docker tag embeddings yourusername/alpine-embeddings:latest
docker push yourusername/alpine-embeddings:latest

Others can run it directly

docker pull yourusername/alpine-embeddings:latest
docker run -p 3000:3000 yourusername/alpine-embeddings:latest

Share as code (this repo)

git clone https://huggingface.co/asusf15/alpine-embeddings
cd alpine-embeddings
docker build -t embeddings .
docker run -p 3000:3000 embeddings

Docker Compose

version: '3.8'
services:
  embeddings:
    build: .
    ports:
      - "3000:3000"
    environment:
      - MODEL=Xenova/bge-small-en-v1.5
    restart: unless-stopped

docker compose up -d

Limits

• Max 128 texts per request
• Max 10MB request body
• Single-threaded WASM (~50-100ms per text)
• First request after cold start takes ~5s (model loading)

License

MIT

Generated by ML Intern

This model repository was generated by ML Intern, an agent for machine learning research and development on the Hugging Face Hub.

• Try ML Intern: https://smolagents-ml-intern.hf.space
• Source code: https://github.com/huggingface/ml-intern